Article delivery and sensing for article sorting machines



R. L. SWARTZ Sept. 8, 1910 ARTICLE DELIVERY AND SENSING FOR ARTICLESORTING MACHINES Filed May 21, 1968 2 Sheets-Sheet 1 INVENTOR RICHARD L.SWARTZ 'k BY W W w ATTORNEYS R. L. SWARTZ Sept. 8, 1970 2 Sheets-Sheet 2Filed May 21, 1968 R 5 2d 4 4 0 8 I 4 United States Patent Oflice3,527,456 Patented Sept. 8, 1970 3,527,456 ARTICLE DELIVERY AND SENSINGFOR ARTICLE SORTIN G MACHINES Richard L. Swartz, Columbia, S.C.,assignor to Universal Business Machines, Inc., Columbia, S.C., acorporation of South Carolina Filed May 21, 1968, Ser. No. 730,754 Int.Cl. B65h 5/22 U.S. Cl. 271-3 6 Claims ABSTRACT OF THE DISCLOSURE Thereis disclosed in the hereinafter specification improved means fordelivering articles such as documents and the like to the conveyingguideway of an article sorting machine. The said means include animproved article delivery station including an article delivery binprovided with a movable article guiding sidewall. Improved means areprovided for detecting articles as they are brought to an articledelivery position such that movement of an article supporting memberWithin said bin is controlled. Finally, means are provided at oradjacent to said station for detecting articles as they are deliveredsuch that a signal, alarm or the like is provided in the event that morethan one article is delivered in a single delivery operation.

FIELD OF THE INVENTION This invention relates to and is usable with highspeed article sorting machines of the type used to sort a large volumeof documents. The documents, e.g., letters, telephone toll cards,checks, and the like may be of the type bearing coded information. Codedinformation is used in conjunction with certain types of sortingmachines for the purpose of distributing the documents to variousselected receiving bins or pockets. Teachings of the general type ofmachine referred to may be found in U.S. Pats. No. 2,668,706, No.2,707,569 and No. 3,288,038.

PRIOR ART In general the type of machines referred to above are providedwith a horizontal conveying guideway having a plurality of documentreceiving bins located therealong. In addition, a plurality of gatestations are also located along the guideway. The said gate stationsinclude tiltable gates and are so arranged that the gates are effectiveto deflect documents moving on the guideway into receiving bins. In sometypes of machines documents are selectively placed in bins whereas inother types documents may be sequentially placed in the receiving bins.

Such machines are usually provided with means for feeding the documentsto the conveying guideway, and in the usual case the document feed meansis located at one end of the guideway; the said means, its associatedapparatus and its general location relative to the machine willhereinafter be collectively referred to as the article delivery stationof the machine. It will be understood that both the apparatus taught bythe prior art and the embodiments of'the present invention describedbelow are located at the article delivery station. Further it will beunderstood that by referring to an article input station it is meantthat the said station may either form a portion of a continuous machinestructure or it can form a separate section that is attachable to andutilizable with the various types of machines referred to above.

In the prior art machines the article delivery station usually includeda document delivery bin provided with four fixed sidewalls and a movableend wall. In order to load the delivery bin it was usually necessary toraise the movable end wall to a document loading position, place a stackof documents to be sorted on the end wall, and

then return the end wall to its initial position. After thesepreparatory operations Were completed the machine operator couldinitiate a sorting operation.

For example, through the use of a keyboard the operator could cycle theend wall up to a document delivery position, i.e., a position wherein asuitable feed mechanism engages the documents and places them on thehorizontal guideway or trackway. In the alternative, the end wall anddocuments supported thereon could be automatically raised to the feedposition by employing a mechanical document sensor in conjunction withthe feed mechanism.

Such sensors usually included a feeler arm positioned above the bin insuch a manner that the stack of documents in being elevated for deliveryengages the feeler to thereby cause power to be disconnected in such amanner as to stop the upward movement of the end Wall. The uppermostdocuments were then fed to the guideway by the feeding mechanism forsorting. Tension was thereby removed from the feeler arm and power wasthereby restored such that the end wall would rise in a stepping manneruntil the stack of documents again effected a power disconnect.

Examples of feeler arm mechanisms used with particular types of documentfeeding mechanisms may be found in U.S. Pats. No. 2,866,640 and No.2,984,481.

Such sensing devices are complicated in operation in that it wasnecessary to move them during the document feed operation such that thefeeding mechanism did not have to overcome the resistance of the sensoras the feeding mechanism removes a document from the stack. Too, becauseof the fixed sidewalls of the delivery bin if it became necessary for anoperator to adjust the documents in the bin the operator could damagethe sensor by reaching into the bin to adjust the documents. Finally,the feeler arm could and does obscure portions of the documents from theoperator. If the portion of the document that is covered by the feelercarries a code the document would either be misdelivered or the operatorwould have to slow down the operation of the machine.

A further problem developed with prior art machines. It was found thatthe feed mechanism for various reasons occasionally would place morethan one document at a time on the guideway. This problem mightespecially occur with very thin documents, i.e., documents having athickness on the order of 7 mils. Under such circumstances documentscould be and were misdelivered to the document receiving bins.

SUMMARY OF THE INVENTION Accordingly, in order to achieve high speedprocessing of a wide variety of documents, it was necessary to overcomethe deficiencies of the machines of the prior art by providing animproved document delivery bin for receiving and storing the documentsuntil the start of a sorting operation which bin would also operate as adocument guide during sorting; by providing an improved system forcontrolling the presentation of the documents to the feeding mechanism;and by providing apparatus for determining that only one document at atime is being fed onto the machines guideway for sorting.

It is therefore a primary object of this invention to provide a noveland useful article delivery station for article sorting machines of thekind hereinbefore referred to.

It is an object of this invention to provide a new and novel articledelivery station provided with improved means for delivering documentsand the like to the conveying guideway of an article sorting machine tothereby improve the operating features and speed of document sorting ofsuch a machine.

It is an additional object of this invention to provide a novel deliverybin structure as part of an article delivery station of or usable withan article sorting machine- It is a further object of this invention toprovide an improved system for controlling the movement of articleswithin an article delivery bin such that they are smoothly and rapidlybrought to an article delivery position for feeding to the guideway ofan article sorting machine.

It is another object of this invention to provide a novel articledetecting mechanism for determining whether more than one document hasbeen placed on the conveying guideway of an article sorting machineduring a single feeding operation.

These and other objects of this invention will be apparent from thefollowing detailed description when read in conjunction with thedrawings in which:

FIG. 1 is a partial perspective view of an article sorting machineprovided with the novel article delivery station;

FIG. 2 is a rear view of a movable sidewall employed in an articledelivery bin shown in FIG. 1;

FIG. 3 is a wiring diagram showing the control power source used inconjunction with an improved document sensor; and

FIG. 4 is a view of an article detector apparatus for determiningwhether more than one document has been placed on the guideway in asingle feeding operation.

Referring now to FIG. 1 of the drawings, an article delivery stationcomprising an article delivery and guide bin 10, document deliverysensing detector 12, 14, a document feed mechanism and a documentdetector 16 are shown located at one end of a horizontal conveyingguideway 18.

The guideway comprises, as in the usual case, a plurality of drivenrollers 20 for conveying documents on the guideway to any of severaldocument receiving bins 22 located along and beneath the guideway. Apair of tiltable gates 24 is shown located in the guideway, and it istheir function to deflect a document moving on the guideway downwardsinto an appropriate receiving bin 22. It is understood that the sortingmachine per se may be any of several types as heretofore mentioned, andit is for this reason that only a schematic representation of theguideway 18, gates 24 and receiving bins 22 has been provided.

In general a document sorting machine of the type depicted in FIG. 1must be provided with an article delivery and guide bin at the articledelivery station which provides the machine operator with complete, fastand easy access to documents placed in the bin for a sorting operation.In order for the machine to be used at an optimum sorting rate theoperator should have full and complete visibility of documents in thedelivery bin 10, and he should have unrestricted access to the bin inthe event of malfunctions, jams, document tilt or distortion.

In the present invention these requirements are met in part by theunique construction of the delivery bin 10. Referring to FIGS. 1 and 2it will be seen that the bin 10 is provided with three fixed verticalsidewalls 26 and a vertically movable sidewall 28. As shown in FIG. 1the sidewalls 26 may in practice be portions of a unitary machine frame30, or the article delivery station may be a separate unit attachable tothe machine frame. In the latter event the fixed sidewalls 26 canconstitute a portion of a framework for the article delivery station.

The movable sidewall 28 is shown in a rear View in FIG. 2. As shown thewall 28 is mounted for vertical movement on a pair of guide rails 32through the use of low friction guide bearings 34. The bearings 34 mayconstitute Teflon (registered trademark) rings or they may be made outof other low friction materials. The wall 28 preferably is made out of alight strong material such as lightweight aluminum. In addition, theguide rails may be mounted internally of the wall 28, or they may befixed externally of the wall and supported by the frame in any suitablemanner, e.g., they may be aflixed to mounting brackets which in turn arebolted or otherwise aflixed to the frame 30.

As shown in FIG. 2, a pair of lock bars 36 and 37 are bolted orotherwise affixed in vertical displacement to each other and to theframe 30. The bars 36, 37 are mounted so as to cooperate with a lockingmechanism 38 mounted on the wall 28 so as to move with the said wall.The locking mechanism 38 comprises an angle member attached to orforming a part of the wall 30 and having a short leg 40 and a long leg42. The leg 42 extends generally in the direction of the bars 36, 37 andis provided with a through hole 44. A fulcrum member 46 is shownsupported by the leg 42 by means of a bearing 48 located in the hole 44.The member 46 is attached to the short leg 40 of the angle member by aspring 50 such that the member 46 may pivot against the spring 50 aroundthe leg 42. A roller bearing 52 or the like is rotatably attached to anend opposite the spring end of the member 46 and is positioned so as toengage the bars 36, 37 when the wall 28 is moved to either of twopositions. Finally, a spring balance 54 is supported on one end by themachine frame 30 and is attached on its other end to the member 46 suchthat when the wall 28 is moved vertically downwards it moves against thespring balance but such movement is aided by the weight of the wall.Conversely, when the wall is moved upward the spring balance acts to aidsuch movement.

In operation the machine operator may quickly and easily lower the wall28 in order to load documents for a delivery operation or to clear andstraighten tilted documents, clear jams and the like. During sorting,the operator can lift the wall 28 such that it in cooperation with thewalls 26 provides guides for the documents as they are raised in thebin. It should be noted that the wall 28 when in the down or loadposition will also provide a partial guide surface.

Referring back to FIG. 1, it will be noticed that the bin :10 isprovided with a movable end wall 56 for supporting documents 58. Thewall 56 is in turn supported by a stem 60 where the stem is movedvertically in guide members 62 through a power take-ofl" from anelectric motor 64. As shown, the stern 60 is provided with a switchoperator 66 for operating a pair of limit switches 68 and 69. Theswitches 68 and 69 constitute up limit and down limit switchesrespectively and when operated out power to the motor such that movementof the stem 60 and hence wall 56 is stopped. In the usual operation thewalls 28 and 56 are lowered for document loading. During documentfeeding and sorting the end wall 56 is automatically raised by aphotoelectric document sensor 12, 14 cooperatingelectrically with themotor 64.

. The photoelectric sensor comprises a source of light 12 arranged totransmit a beam of light to a photocell 14. The detector is so arrangedthat as the stack of documents 58 is moved vertically upwards in the bin10 the uppermost documents will, when in position for feeding to theguideway 18, break the light beam.

1 Referring now to FIG. 3 it will be noticed that the light source 12and phot'ocell 14 are electrically connected to an AC. source T T by astep down transformer 70. The photocell is connected in series with arelay 72 having contacts 72a. The circuit of FIG. 3 is shownde-energized. Thus, with light impinging on the photocell 14, thecontacts 72a reverse. Assuming it is desired to raise the stack ofdocuments, a switch 74 is closed on up movement contacts 74:: tocomplete a circuit from T through a relay 76, the normally closed uplimit switch 68, and the now reversed contacts 72a to T thus energizingrelay 76 and causing its contacts 76a to reverse. Power is now appliedto the motor 64 from the positive terminal of a battery 78, throughcontacts 80c of a de-energized relay 80, the motor 64, the reversedcontacts 76a, a speed control resistor 82, contacts 80a and to thenegative terminal of the battery 78. It is believed that it isunnecessary to trace the current path for a down movement of the end Iwall of the bin 10.

As should be readily apparent from FIG. 3, when a document in the stack58 interrupts the light beam the relay 72 de-energizes returning itscontacts 72a to the position shown in FIG. 3. This action in turn causesde-energization of the relay 76 which thereby returns its contacts 76ato thus break the series current path to the motor 64. In this mannerthe movement of the end wall is rapidly stopped such that the uppermostdocuments in the stack 58 are in the proper position for being fed fromthe stack onto the guideway 18. It should be apparent that this systemprovides improved sensing and a much more accurate con trol over theplacement of documents in a delivery bin than was provided by the priorart mechanical sensor. And, the operators field of vision for thedocument is unimpaired with the improved system thus allowing theoperator to fully concentrate his attention on the coded portions of thedocument as he operates bin selector keys on a keyboard.

As has been stated heretofore, the feed mechanism may be any one ofseveral dilferent types. For example, it can he a vacuum systemincluding a cup mounted for vertical and horizontal motion as shown inU.S. Pat. No. 2,984,- 481. A feed mechanism of the type described in thepatent is illustrated diagrammatically in FIG. 1 as the unit 15; thedetails of the mechanism may be obtained from said U.S. patent. In sucha system the pick-up and feed cup is operated in conjunction with thecontrol system utilized to select and operate guideway gates 24. Thus ata proper point in a feed cycle the cup moves downwards into contact withthe uppermost document in the stack 58, vacuum is applied, and the cupthen picks up the document and carries it to the guideway. When thedocument is properly positioned relative to the guideway the vacuum isremoved and the document is thereafter propelled down the guide way bythe powered rollers 20.

On occasion the feed mechanism picks up more than one document at a timeduring a single feeding operation of the types described above. Thissort of malfunction is most likely to occur when the documents are verythin, e.g., when they have a thickness of approximately 0.007 inch. Forobvious reasons a malfunction of this type is highly undesirable, e. g.,it can result in the placement of documents in the wrong receiving bins.Also, because of the very high speed operation of the sorting machines,because of the thinness of the documents, and because of thediscontinuity in document fiow, i.e., an electronic analog might be aseries of pulses, it is a very difficult problem to detect a malfunctionof the type here referred to. Detectors used to determine variations incontinuous flow machines are generally not sensitive enough to determinewhether one or two documents have been placed on the guideway in asingle feeding operation, in an article sorting machine.

A novel detector system 16 for quickly determining whether such amalfunction has occurred is shown in FIG. 4. Since it is the function ofthe detector system to determine whether more than one document has beenplaced on the guideway 18 in a single feeding operation it wasdetermined that the measurement that should be made would be one ofthickness, i.e., if two similar documents were inadvertentlysuperimposed on each other the total thickness would be equal to twicethat of a single document, e.g., 14 mils.

I therefore decided to mount two rollers such that any document placedon the guideway 18 has to pass through the rollers. As shown in FIG. 4 athickness detector roller 84 is mounted on a shaft 86 such that theroller 84 is in direct and rolling contact with a driven roller 20 inthe guideway 18. The shaft 86 is journaled in a pivotable supportingmember 88.

The member 88 is mounted on a pivot shaft 90 extending transverselythrough the member 88. The pivot shaft is supported for rotation in apair of bearing housings 92 secured to a guideway rail 94. The guidewayrail is either supported by the machine frame 30 or it may be part ofthe said frame. A bracket 96 is secured to a bearing housing 92 suchthat it extends in the direction of the member 88. A spring support bar98 is secured to the bracket as by being welded thereto such that itextends over the member 88. A spring 100 is attached to the bar 98 andthe member 88 and it serves to hold the bar against the bearing surfacesin the bearing housings, i.e., it eliminates any clearance space in thebearing such that the roller will be able to immediately react to adocument passing between the rollers 84 and 20.

A pair of transversely extending tongues 102 and 104 are mountedopposite each other and on the extreme end of the bracket 96. The lowertongue 102 is provided with a hole at its outer end for supporting aswitch 106 which may be an electric switch such as a microswitch. Themember 88 is pressed against an operating button 108 of the switch 106by a set screw 110 mounted in a threaded hole located in the uppertongue 104. Thus it will be apparent that the degree of documentthickness corresponding to a malfunction in feed as defined above can beregulated by adjusting the screw 110 to thereby vary the pressureexerted on the switch button 108 by the member 88.

If the article delivery station is supplying documents having an averagethickness of 7 mils. to the guideway 18 then the pressure on the switchis adjusted to detect a thickness of 10-14 mils. Accordingly, if twodocuments are fed onto the guideway the angle through which the roller84 and its supporting members 86 and 88 pivots is sufficient to operatethe microswitch. The microswitch can be connected to perform any of anumber of functions in the sorting machines control circuits. Forexample, U.S. Pat. Nos. 3,021,509 and 3,259,238 disclose controlcircuits usable with certain types of article sorting machines. Asexplained in the said patents it is desirable on some occasions tocancel selecting signals used to select particular gates 24 (FIG. 1). Itwill be recalled that by selecting particular gates 24 the operator hasthus selected particular document receiving bins. If a cancel signal isinserted at the control keyboard then either all previously selectedgates are closed or in some cases all previously selected gates in aparticular section of the guideway may be closed.

In the present invention the switch 106 can be connected into thecontrol circuitry such that when it is operated it will provide a cancelsignal to thereby effect a closing of all gates 24 such that the two ormore documents that were improperly fed onto the guideway proceed downthe guideway and are deposited in a reject bin. Obviously, themicroswitch could be wired into the circuitry to perform other functionsas alternatives to that explained above. For example, it may be used tolight a warning lamp or it might be used to shut down the entire machineby performing a power disconnect operation.

In summary then what is provided by this invention is a new and novelarticle delivery station including a novel delivery and guiding bin foran article delivery machine, a novel sensing circuit and means forcontrolling the positioning of documents within said bin and a noveldetector system for detecting feed malfunctions.

What is claimed is:

1. Apparatus for delivering articles to be sorted to an article sortingmachine, the machine comprising a conveying guideway along the length ofwhich are disposed a plurality of article receiving bins and a pluralityof article deflecting gates for diverting articles on said guideway intosaid receiving bins, said apparatus comprising at least one articledelivery station including:

at least one article delivery bin including three fixed sidewalls and afourth sidewall, the fourth sidewall being movable relative to the saidfixed sidewalls between an article guiding position and a bin accessposition, said article delivery bin further including a driven movableend wall for supporting and delivering articles to said guideway;

means positioned adjacent to said guideway and responsive to articlessupported by said movable end 7 wall for controlling the position ofsaid end wall within said bin;

means for removing individual articles from said bin and delivering sameto said guideway; and

means for detecting and responding to a physical characteristic ofarticles delivered to tbe guideway and to provide an indication of amalfunction in the event that said article delivery means feeds morethan one :article at a time in one delivery operation.

2. Apparatus according to claim 1 wherein said fourth sidewall ismounted on guide rails for low friction movement between the two saidpositions, said fourth sidewall also being provided with spring balancemeans, and wherein locking means are provided for locking the saidsidewall against movement in each of the said two positions.

3. Apparatus according to claim 1 wherein said means for controlling theposition of said movable end wall comprises photoelectric means mountedso as to be responsive to said articles to thereby provide signals forcontrolling movement of said end wall.

4. Apparatus for delivering articles to be sorted to an article sortingmachine, the machine comprising a conveying guideway along the length ofwhich are disposed a plurality of article receiving bins and a pluralityof article deflecting gates for diverting articles on said guideway intosaid receiving bins, said apparatus comprising at least one articledelivery station including:

at least one article delivery bin, said bin including a plurality ofsidewalls at least one of which is movable relative to the others, and adriven movable end wall for supporting and delivering articles to saidguidey;

means positioned adjacent to said guideway and responsive to articlessupported by said movable end wall for controlling the position of saidend wall within said bin;

means for removing individual articles from said bin and delivering sameto said guideway; and

means for detecting and responding to a physical characteristic ofarticles delivered to the guideway to provide an indication of amalfunction whenever the article delivery means feeds more than onearticle at a time in a delivery operation, the said responsive meansincluding a pair of relatively adjustable rollers supported along saidguideway such that an article moving down the guideway passes betweenthe rollers, one of said rollers being pivotally mounted to effectenergization of a switch upon being pivoted through a predeterminedangle by articles passing down the guideway.

5. Apparatus for delivering articles to be sorted to an article sortingmachine, the machine comprising a horizontal conveying guideway alongthe length of which are disposed a plurality of article receiving binsand a plurality of article deflecting gates for diverting articles onsaid guideway into said receiving bins; said apparatus including:

at least one article delivery station positioned at an article inputportion of said guideway, said station including means for deliveringindividual articles one by one to said guideway; and

a multiple article detector mounted at the input portion of saidguideway and including a roller located in the guideway, a pivotablymounted sensor member mounted such that an article on said guidewaypasses between said sensor and said roller, and means positionedadjacent to said sensor and operated thereby to provide a signal forindicating the presence of multiple articles delivered by said means fordelivering individual articles during a single delivery operation.

6. Apparatus according to claim 5 wherein means are provided foradjusting the position of the sensor member relative to said roller.

References Cited UNITED STATES PATENTS 2,707,142 4/1955 Waite 27l-623,185,473 5/1965 Miaskof 27156 3,339,916 9/1967 Tregay 271-61 RICHARD E.AEGERTER, Primary Examiner

